fix: should only check valid fragments in markdown (.md) files

test/index.test.js

@@ -123,6 +123,11 @@ test("ensure the rule validates correctly", async (t) => {
         fixturePath:
           "test/fixtures/valid/existing-heading-fragment/existing-heading-fragment.md",
       },
+      {
+        name: "should only parse markdown files for fragments checking",
+        fixturePath:
+          "test/fixtures/valid/only-parse-markdown-files-for-fragments/only-parse-markdown-files-for-fragments.md",
+      },
       {
         name: "with an existing file",
         fixturePath: "test/fixtures/valid/existing-file.md",